As is well known, the packets of cigarettes produced on a packeting line are checked during their transit along the line to ensure that their shape is correct and that all their required component parts are present. Following these checks, any packets found to be defective are expelled from the packeting line at appropriate discarding stations, and are then replaced at a replacement station with sound packets, to maintain the continuity of succession of the conveyed packets. Maintaining this continuity is necessary to prevent problems arising at the subsequent working stations to which the packets are conveyed, in that for example the arrival of an incomplete group of packets at a subsequent working station would result in the inevitable discarding of the entire group.
Apparatus for replacing discarded defective packets with sound packets are known, for example from GB patent 2,021,082, in which the sound packets to be fed into a conveying line to replace the missing packets are contained in one or more stores, from which transfer means extract the packets in succession as required. Such apparatus are however considerably bulky, complicated and costly, because of the presence of said stores and the transfer means for extracting the packets from the stores.
In addition, the packets have to be periodically loaded into the said stores by an operator, which means that a person must be assigned to periodically check the degree of filling of the stores and to fill them manually.